Managed storage modules, such as managed NAND storage modules, provide many benefits over using raw memories such as flash NAND memories. Managed storage modules, which typically include a storage controller combined with NAND memory in the case of managed NAND or other types of memory in other cases, provide several benefits to device manufacturers. The storage controller hides the details of the memory (e.g., NAND) and provides the intended interface and other features, such as error-correcting code (ECC) support without the device manufacturers having to implement those features on the host side (e.g., a smartphone or a tablet, an SoC). Additionally, managed storage modules allow new advanced features to be implemented in the storage controller without the host necessarily having to be aware that the features exist. The advanced features may either be activated or not by the storage controller depending on whether the host supports the features. Thus, managed storage modules improve backwards compatibility.
Examples of managed storage modules (e.g., managed storage devices), and in particular managed NAND storage modules, include embedded multimedia cards (eMMC), Universal Flash Storage (UFS), solid-state drive (SSD) modules. These modules are used in wide variety of applications like mobile phones, Global positioning system (GPS) devices, media players, PCs, and servers for storing the operating system code, applications, and user data, such as, photos and videos. Along with the data visible to the host device, operational code/firmware (FW) of the storage module itself is stored in the memory of the storage module. Additionally, other important data, which is used to operate the memory module, such as register data and address translation data, may be stored in the memory.
The increase of interface bandwidth and introduction of caching has improved the sequential read/write and random write performance of a managed storage module. Queuing commands may also improve the random read performance. However, this depends on a capability of the system to efficiently queue commands and, to some extent, a capability to predict how the storage will be accessed in the future. U.S. Pat. No. 8,560,778, filed Jul. 11, 2011, introduces some methods for informing the storage module to pre-fetch data before a new command is received. The content of this patent is incorporated herein in its entirety.